It is conventional to provide a source of recycled cooling water for cooling the absorber and condenser in an absorption refrigeration system. Typically the cooling water flows through coils or other heat exchange apparatus associated with the solution in the absorber and with the vapor in the condenser. The relatively warm water must itself then be cooled, and conventionally this is accomplished by means of a cooling tower where heat is rejected to the atmoshphere during evaporation of a part of the water. The present invention provides a system in which the absorber or condenser and preferably both are cooled by direct contact with evaporating liquid, thereby eliminating the cooling tower and its connections to the system. This results in a savings in space requirements and in installation costs.
A further feature of the invention, which also reduces space requirements, is an improved arrangement in which the absorber is constructed of annular shape and in which the generator and condenser are located centrally within the annular absorber. This arrangement is particularly compatible with the abovedescribed arrangement in which the external surfaces of the absorber and condenser are cooled by contact with evaporating liquid.
The above features can be obtained by a system in which the components are arranged in a common housing through which a stream of ambient air is passed by a fan or the like and in which a stream of water is directed onto the surfaces of the absorber and condenser so as to form a film of evaporating water on these surfaces. The water vapor passes out of the housing with the air stream and the unevaporated water is collected and recycled to the surfaces to be cooled. The absorber is preferably an annular vessel disposed with its axis vertical and surrounding the other components. In operation solution weak in refrigerant flows down the inner surface of the annular vessel while absorbing refrigerant vapor being passed into the vessel and while being cooled by heat exchange with the evaporating liquid film on the outside of the vessel.
The condenser is preferably a closed shell over which the evaporating cooling liquid flows. The generator is preferably a smaller vessel located within the upper portion of the condenser and constructed to expel refrigerant vapor into contact with the inner surface of the wall of the condenser so that condensed refrigerant flows down this surface to the lower portion of the condenser. The heat source for the generator may be a stream of hot fluid, such as steam or hot water, passing in heat exchange relationship with the solution in the generator.